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Discussion Starter #1
As the title implies, I decided to change my header gasket last night. I managed to undo all the bolts without jacking the engine or removing the engine mount. I took out all of the top ones and just backed out the bottom ones. Got the gasket in ok, but when I went back to thread the last bolt, I ended up cross-threading it and now it goes in only halfway and crooked. It sucks because these bolts sometimes slide right in, then get a little tough, then continue to slide right back in. I thought I had hit one of those "tough" spots, then realized what I had done.

I'm thinking that the #1 way to take care of this is to remove the head and have it re-tapped. That just isn't going to happen for awhile. Anyone have any ideas, and do you think this will cause the header to still leak? These gaskets are about 3 times thicker than the ones I had before and the ports match much better. I've had one loose bolt and not have a leak before, so I'm vaguely optimistic about this.

Gotta love these character building exercises. :frustrated:
 

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you should be able to just tap it where it is,they make short taps....good luck.
 

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Pull the header back off. Just try running a tap through there and see what happens.

When you put the gasket back in, use some high temp silicone sealant.
 

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+1 on tapping it in place. Get one with a good lead taper and it should start pretty easily.
 

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Just chasing the threads with a tap should fix the problem. Run the tap in, and back it out. A little grease wouldn't hurt.
 

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Discussion Starter #6
Anyone know what size tap I may need? I have a tap and die set, but I'm not overly versed on the sizes.
 

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If you can get at it, tap the hole with the header bolted on. The flange will serve as a guide for the tap.
 

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Anyone know what size tap I may need? I have a tap and die set, but I'm not overly versed on the sizes.
Does your tap and die set have a metric pitch gauge? If so, you can just measure the bolt that came out and see which threads line up with the gauge. If not, try fitting the bolt through one of the dies. You'll then be able to tell what the thread diameter and pitch are. Just use that same size tap to chase the threads.
 

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They look to be M8x1.25. But don't quote me on it.
 

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Cool. Thanks. I'll give it a whack and let you all know how it turns out.
Just in case, to chase a thread, add a little oil or grease to the tap, then gently start it to threading by hand. Once it's in the hole, put the T-handle on the tap and turn it until you feel it engage the bad portion of the thread. Turn the tap one quarter turn at a time. Then back it out about a half turn. Continue threading the tap in one quarter turn at a time and backing it out. That will keep you from buggering up the threads.
When you start feeling a lot of resistance, you're probably at the bottom of the tapped hole. It's probably only a couple of bad threads, so you should be able to feel the tap free up once you get past the bad section.
Hope that helps.
 

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Joel I like the header "What should I do" Don't do it again. :hihi:
But seriously you have all the good advice you'll need. Leave them on and you can use a open end wrench on the square head or even a square nut socket on a ratchet. I'd spray some brake clean to clean out the hole of any chips. Make sure its dry before you start it up so you don't set your car on fire. :nono:
 

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Discussion Starter #13
Just an update, I GOT IT IN!!!! Took me a few days to get around to it, but it only took about 20 min. I had to get a shorter tap handle, but all in all it went pretty smoothly. Header is on nice and tight now. Everyone cross your fingers that this relieves the stupid ticking in the engine bay.

Thanks!!
 

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what kind of headers did you install??? let me know your results/opinions, thanks.

Oh yea, glad to hear you got the cross threaded bolt thing sorted out. But remember "Cross Threads Are Better Than No Threads".
 

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Discussion Starter #15
what kind of headers did you install??? let me know your results/opinions, thanks.

Oh yea, glad to hear you got the cross threaded bolt thing sorted out. But remember "Cross Threads Are Better Than No Threads".
I shot you a PM with my thoughts on the headers.
 

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Just an update, I GOT IT IN!!!! Took me a few days to get around to it, but it only took about 20 min. I had to get a shorter tap handle, but all in all it went pretty smoothly. Header is on nice and tight now. Everyone cross your fingers that this relieves the stupid ticking in the engine bay.

Thanks!!
Super... definitely been having your share of tough luck lately.
 

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Coolio... and no disassembling the engine, valvetrain, taking the head off, waiting for the shop to get to it, then reassembly.
 
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